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Jan. 31, 1961 Filed May 19, 1955 H. E. CORNISH ET AL 2,969,702 APPARATUSFOR RUNNING THREAD-JOINTED OIL WELL STRINGS INTO AND OUT OF OIL WELLS 8Sheets-Sheet 1 I l .964; 109 i D 12a: 87 y f {"123 v KILL- I 1 t I .93l. J I. 1-. 7

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H. E. CORNISH ETAL 2,969,702 APPARATUS FOR RUNNING THREAD-JOINTED on,WELL STRINGS INTO AND OUT OF OIL WELLS 8 Sheets-Sheet 2 Jan. 31, 1961Filed May 19, 1955 Jan. 31, 1961 H. E. CORNISH ETAL 2,969,702

APPARATUS FOR RUNNING THREAD-JOINTED OIL WELL STRINGS INTO AND OUT OFOIL WELLS Filed May 19, 1955 8 Sheets-Sheet 3 Jan. 31, 1961 H. E.CORNISH ETAL 2,959,702

APPARATUS FOR RUNNING THREADJOINTED OIL WELL STRINGS INTO AND OUT OF OILWELLS Filed May 19 1955 8 Sheets-Sheet 4 27/4245: 6. Gene; 41040 f620555 50 420 A. MPsaw Jan. 31, 1961 H. E. CORNISH ET AL 2,969,702APPARATUS FORRUNNING THREAD-JOINTED on.

WELL STRINGS INTO AND OUT OF OIL WELLS 8 Sheets-Sheet 5 Filed May 19,1955 VENTORJ h nezv f. Cozy/5H C'HAEL 5: 6'. 6/245; #42040 620:5! ion420 M 6 AM 1961 H. E. CORNISH TA APPARATUS FOR RUNNING THREAD-JOINTEDOIL WELL STRINGS INTO AND OUT OF OIL WELLS I 8 Sheets-Sheet 6 Filed May.19 1955 I zgulf a I" a 1i I if V 136 129 m i J 11/ J 14 J44 12.94

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WELL STRINGS INTO AND OUT OF OIL WELLS Filed May 19, 1955 8 Sheets-Sheet8 2/? Tom Mame #902904 /c 1.67 eisiil/o/i M Ton/e 2 10 53 [LEI/A701? INV EN TORS A4722? 5, Cae/v/sh 4/: #4555025 044545: 6 Game;

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United States Patent G APPARATUS FOR RUNNING THREAD-JOINTED gllllllsiELLSTRINGS INTO AND OUT OF OIL Harry E. Cornish, Palos Verdes, Charles 'G.Graef, Downey, Harold F. Groehe, Inglewood, and Edward H. Simpson, LosAngeles, Calif assignors to & M Machine Company, Inc., 'Los Angeles,Calif., 21 corporation of California Filed May 19, 1955, Ser. No.509,652

Claims. (CL-.81-53) This invention relates generally to oil well toolequipment, and more particularly to apparatus for running thread-jointedoil well strings such as drill pipe, tubing or rods into and out of oilwells. The invention will be chiefly disclosed in a present applicationto the running of so called slim hole drill pipe stands into and out ofoil wells in exploratory drilling operations, but without anyimplication of limitation thereto whatsoever, since the invention isequally applicable to standard drill pipe drilling, to pump tubing, andto sucker rods.

As applied to any of these operations, the primary object of theinvention is the provision of pipe or rod handling machinery whichgreatly facilitates the running of thread-jointed pipe or rods, bothinto and out of an oil or water well, at once speeding up the operation,and decreasing the required personnel.

Taking the case of the drilling application for purpose of illustration,the procedures involved in running drill pipe are well known. Drill pipecomes in joints or sections of predetermined length, each of which has afemale coupling element, at its upper end and a male coupling element atits lower end. These joint elements are frequently of a conventionaltype known as box and pin, respectively. Two to four of these joints arecommonly secured together to give a stand, of convenient length forhandling within the derrick. In running in pipe, i.e., making joint,such joints or stands are added to the drill string one at a time bymethods and equip ment now too well known to require description herein.Briefly, while the string is supported by slips in the rotary table, anew joint or stand is lowered into position by an elevator, the pin onits lower end being stabbed into the box on the upper end of thesupported string, and the new joint is then spun into position. Thejoint is tightened by means of tongs. Power tongs and spinners have beenprovided to facilitate these operations, and are generally side-openingin order to facilitateclamping onto the pipe. Reverse procedures areemployed in running out the pipe, i.e., breaking -joint. Theseoperations require various pieces of known equipment, whose manipulationrequires a number of men on the derrick floor and in the derrick.

Briefly stated, the invention provides a slip bowl equipped with poweroperated slips at the well head, conveniently positioned in the rotarytable in the case of a drilling operation, a power tong or spinner,having a slip bowl equipped with power operated slips, mounted over thewell head, and power means for vertically reciprocating the power tongthrough a predetermined stroke. In making joint, the power tong is runto an upper position, just above the .box on the upper end of the pipestring suspended by the slip bowl in the rotary table. By'a loweringoperation of the drill-pipe elevator (which is carrying the stand to beadded), the coupling pin on the lower end of the pipe stand to be addedis then stabbed through the power tong slip bowl (whose slips are inopen position), into the box on the upper end of the-suspended pipestring. The tong slips are then set to grip the pipe, and the tong isoperated to spin in the new stand. The slips in both bowls are thenreleased, transferring the load of the string to the drill pipe elevatorengaged with the coupling box at the top of the added stand. The powertong is then lowered about the pipe string to the lower limit of itsstroke. The drill pipe elevator then lowers the string until thecoupling box at the top is just above the power tong in the loweredposition of the latter, it being noted that the purpose of theaforementioned lowering of the power tong was to clear the area for thejust described lowering operation of the drill pipe elevator. 'Ihe slipsin the table sup ported bowl are then set about the pipe, the drill pipeelevator disengaged and raised, and the power tong-then raised to itsinitial or upper position, after which the sequence is repeated. Similarbut reverse procedures are performed in breaking joint.

A hydraulic cylinder and piston assembly is provided for mounting andfor vertically moving the power tong between its upper working positionand its lowered position, and torque arm means are provided inconnection therewith for resisting the torque reaction that is exertedwhen the power tong is engaged in spinning the pipe. The hydrauliccylinder and piston assembly is mounted on the rotary table frame, and atorque linkage is provided by which the torque transmitted to theassembly by the aforementioned torque arm is ultimately taken orresisted by said frame. This torque linkage is arranged for quickdisconnection to permit swinging of the power tong away from the centerof the drill hole whenever required. a

The invention further provides a system by which all of theaforementioned operations are carried out by power instrumentalitiesunder the control of single operator, reducing the necessary crew tothis control operator and one additional man in the derrick to handlethe pipe stands.

The invention will be better understood from the following detaileddescription of one illustrative embodiment thereof, reference for thispurpose being had to the accompanying drawings, in which:

Fig. 1 is a perspective view of a drilling apparatus in accordance withthe invention;

Fig. 2 is a transverse section taken in accordance with line 2-2 of Fig.1;

Fig. 2a is a detail section taken .on line Za-Za .of Fig. 2;

Fig. 3 is a plan view of a portion of the rotary table and slip bowltaken in accordance with line 3-3 of Fig. 2;

Fig. 4 is a section taken on line 4-4 of Fig. 3;

Fig. 5 is a section taken on line 5-5 of Fig. 3;

Fig. 6 is a broken section taken in accordance with line 6-6 of Fig. 3;

Fig. 7 is a detail section taken in accordance with the line 7-7 of Fig.6;

'Fig. 7a is a view showing a wedge slip face prior to grooving;

Fig. 8 is a section taken on line 8-8 of Fig. 6;

Fig. '9 is a section taken on line 9-9 of Fig. 6;

Fig. 10 is a detail elevation of a slip;

Fig. 11 is an enlarged portion of the slip of Fig. 10;

Fig. 12 is a detail of a slip mounting pin;

Fig. 13 is a plan view of the power tong, taken in the direction of thearrow 13 of Fig.1;

Fig. l4 is an elevational view taken in accordance with line 14-14 ofFig. 13;

Fig. 15 is a section taken inaccordance with line 15-15 of Fig. 13;

Fig. 16 is an elevational view, partly in section, showing .the powertong elevator;

Fig. 17 is a section taken on line 1717 of Fig. 16;

Figs. 18 and 19 are diagrammatic views of the apparatus showing twoillustrative operating positions thereof;

Fig. 20 is a diagrammatic view of the hydraulic control system of theinvention; and

Fig. 20a is a diagram of a valve of the system of Fig. 20, shown inneutral position.

Referring first to Fig. 1, there is designated at T a conventionalrotary table, having a supporting frame or platform 20 at the well head,the derrick and the usual elevator, together with other conventionalequipment, being omitted from the drawings.

7 Extending down through a bushing or slip bowl 22 in rotary table T,and positioned therein as shown, is a section 23 of worm hole drillpipe, having at its upper end a box coupling member 24, the pipe section25 immediately above being understood to be threaded at its lower endand to be screwed into the conventional threads inside the box 24.

The lower end portionof the upper pipe section 25 is surrounded by apower tong 28, carried through the agency of a right angle torque armassembly 29 from a tong elevator E comprising a vertically disposedhydraulic cylinder 30 movable vertically on stationary piston 31 whichis rigidly mounted on a flange 32 secured to the rotary table platform20.

The rotary table is shown for illustrative purposes as having in the topa squared aperture 34, below which is a circular bore extendingdownwardly through the bottom of the table, and between the aperture 34and the bore 35 is an annular groove 36. The squared aperture 34 isrounded at its corners on arcs which are coincident with the groove 36,as clearly shown in Fig. 3.

The bushing 22 has at the top a square flange 49 receivable through thesquare aperture 34 of the table, and below said flange is an annularshoulder 41 snugly receivable inside the table bore 35. At a substantialspacing below the flange 40, the bushing 22 also has a circular flange42 snugly receivable inside the bore 35. The bushing 22 is introducedinto the bore 35 of the rotary table by lowering it through the squaretable aperture 34, its squared flange 40 being oriented properly toregister with the square aperture 34. When the flange 40 has engaged theseat 43 formed at the bottom of groove 36, it is rotated through to theposition shown in Fig. 3, so that the corner portions of the bushingflange 40 are then underneath the downwardly facing shoulder 44 formedby the upper side of the groove 36. The bushing is then looked in suchposition by means of pins 45 mounted in flange 40 and projectingdownwardly into suitable grooves 46 formed in the upper portion of thebore 35.

The bushing 22 is generally cylindrical in exterior shape down to theflange 42, below which it has a reduced intermediate section 47, and thelatter is joined through a reduced, stepped portion '48 with a finallower tubular end portion 49 of still further reduced diameter. Adownwardly tapering opening 50 extends downwardly into the bushing fromits upper end, completing the tapered slip bowl, which is generallydesignated at B. This slip bowl terminates just below the intermediateportion 47 of the bushing, in the general arrangement clearly shown inFig. 6. A centrally apertured cover plate 22a is secured to the bushingover the opening 50.

Mounted in the tapered slip bowl are a plurality of slips 51, six innumber in this instance. Each such slip comprises a concave faced plate52, provided with a multiplicity of pipe gripping teeth 52a (Fig. 11).These teeth are conveniently formed by first spirally grooving thesurfaces as though a V-shaped screw thread were to be formed, and thenvertically grooving the surfaces with parallel spaced V-grooves.Preferably, prior to the vertical grooving, the concave surfaces of theplates 52 are modified by forming them, top to bottom, with a flattenedcentral region 52b, merging through smooth curves with ,4 flattened wingregions 520, as shown in Fig. 7a. Joined to the back of each plate 52and extending perpendicularly thereto is a wedge shaped mounting plate53. Integrally formed with the top of the latter is a hook-like mountingmember 54 forming a horizontal jaw or opening 55 which slidably receivesor engages a peripheral edge portion of a spider plate 56, the slipsbeing suspended from the spider plate, and being slidable in horizontaldirections thereon as they move radially in and out during verticalmovement in the tapered slip bowl.

The angular rearward edge portion of each slip 51 is formed with notches57 to receive spaced collars 58 on a bearing pin 59. This pin has apoint on its upper end to engage in a socket in the heel of the hookmember 54 (Fig. 6), and at its lower end, has a reduced pin 62 engagingin a hole in a clip 63 secured to the bottom of the slip. The bearingpin is thus detachably assembled with the slip. The rearward edgeportions of the plate 53, between the notches 57, are arcuately formedand machined to have bearing on the pin 59, as shown in Fig. 7, and theopposite faces of the collars 58 are provided with machined surfaces soas to afford a free working fit against opposed similarly machinedsurfaces on the member 53, whereby the slip is not only backed up by thebearing pin 59, but also relatively rotatable thereon with a freeworking fit. The collars 58 of the hearing pins 59 are slidably receivedin half-round longitudinal grooves 65 formed in the slip bowl, it beingunderstood that there is one such groove for each wedge slip. Inoperation, when the toothed concave surfaces of the slips are engagedwith the pipe, any tendency for rotation of the pipe in either directioncauses the slip to rock slightly on its bearing pin 59, thereby bringingthe angular wing portions 52c of the toothed gripping surface 52 intowedging engagement with the pipe, so as to atford, in eifect, aself-energizing lock against the pipe.

Spring arms 66 mounted on the underside of spider plate 56 engage pin 67on opposite sides of wedge slip plate 53 to hold the wedge slip assemblyin proper working position with the collars 58 seated in the groove 65.When the slips are lowered, by lowering of the spider plate 56, theslips move radially inward, their mounting plates sliding radiallyinward on the spider plate; and when the spider plate is elevated, thesprings 66 expand them by pressing radially outward on the pins 67.

The arms 78 of spider plate 56 (Fig. 8) are formed with radial notches71 to slidably receive the reduced shank portions 72 of headed rods 73extending downwardly through vertical bores 74 which are formed in theslip bowl, the'lower portions of these bores 74 opening to the outsideof the slip bowl below the flange 42, as indicated.

On the reduced lower end portions of rods 73 be tween shoulders 81 and abearing ring 82 surrounding and slidable on bushing portion 49, is anannulus 84, the parts being secured in assembly by nuts 85 screwed onthe lower ends of rod portions 80. The annulus 84 carries the inner racering of radial and thrust bearings 86, the outer race rings of which areaccommodated within an elevator collar 87, the latter being positionedby means of a flange 38 at the top, engaging the outer race ring of theupper bearing 86, and a retainer ring 89 at the bottom, engaging theouter race ring of the lower bearing 86.

Collar 87 is formed with diametrically opposed headed trunnions 90,engaged by the bifurcated forward ends of the two arms 91 of a yoke 92pivotally mounted at 93 to form a lever structure actuated by ahydraulic ram 94 for raising and lowering the collar 87, and therefore,through rods 73 and spider 56, the set of slips 51. In the constructionshown, Fig. 2a, the bifurcated forward end portions of the arms 91 arebacked up by similarly bifurcated-plate 91a, and are furnished on theirouter sides with spring arms 91b, fastened at one end to the arms 91, asat 91c, and provided with circular apertures 5. 91d which engage overtheheads of trunnions 9 to fix the linkage to the latter. These spring armsmaybe sprungzout, as shown in :Fig. 2a, .to facilitate .quickdisengagement of the arms 91 from the trunnions.

Asshown in Fig. 4, the arms 91 are pivotally mounted at 93 on a .pin 95carried by the lower end of'a link 96 depending from and pivotallymounted at its upper end on a pin 97. The pin '97 is mounted in the endof a supporting plate 98 secured to a lower wall 99 of the rotary tableas by screws 100.

The ram-94 (Fig. 5) comprises a cylinder 1B2 containing a piston 103 ona connecting rod 104 which is pivotally mounted at its upper end on apin 105 mounted in a fitting 1116 secured to mounting plate 98. To thelower end of cylinder 102 is secured a cross-head 107 furnished withtrunnions 108 which pivotally support lever arms 91 at pointsintermediate their ends. Hydraulic fluid is introduced alternately toopposite ends of cylinder 1112 through suitable ports from fluid linesindicated at 109 and 110m Fig. 2, under control of a suitable valve.

It will be evident that introduction of fluid to the lower end ofcylinder 102, for example, will lower the cylinder 132 on piston 103,moving the cross-head 107 and the arms 91 downwardly, and so loweringcollar 87, and therefore annulus 84, which in turn draws the rods 73downward, and with them the spider 56 and slips carried thereby. Theslips are elevated by opposite motion of the linkage when fluid isintroduced to the upper end of the cylinder. It will be noted that thelinkage as described permits free rotation of the rotary table T andbushing 22 without breaking the connection to the means ,for lowering orelevating the slips, the ring 84 on the elevator rods 73 turning freelywithin the elevator collar 87 during rotation of the table. -By themeansprovided, therefore, the slips can be contracted or expanded to engageor disengage the pipe by operation of a simple hydraulic control valve.

The power tong and its elevator will next be described.

Referring to Fig. 15, the power tong utilizes a tapered slip bowl andslips, together with actuating means therefor, substantially identicalwith that employed in the rotary table, and heretofore described indetail. Thus, a tubular housing or slip bowl is provided, differing inonly minor particulars from the bushing 22 previously described. Thisslip bowl 125 has tapered opening 126, slips 127, spider plate 128,elevator rods 129, ring 129a on the lower end of rods 129, annulus 130and elevator collar 131, with bearings as shown intervening between themembers 130 and 131, all as earlier described in connection with thecorresponding device utilized in the rotary table. Also, in a mannersimilar to that described for the corresponding device in the rotarytable, the collar 131 is adapted to be elevated and lowered by leverarms 132 pivotally mounted at 133 at the lower end of a link 134, whichis in turn pivotally mounted at 135 on a mounting fixture 136, which inthis case is bolted to the underside of a mounting plate 137 secured tothe lower portion of the power tong housing 138. A hydraulic ram isprovided for operating the lever arms 1 32 and comprises a cylinder 139containing a piston 14!) on a connecting rod 141 pivotally mounted at142 on the fitting 136. The lowerend of cylinder 139 carries cross-head143 furnished with trunnions 144 connected to intermediate points of thearms 132, all in the same manner as described in connection with thehydraulic ram mechanism for operating thearms 91 of the deviceassociated with the rotary table. Further detailed description of thepresent device is accordingly deemed unnecessary.

Slip bowl 125 has tightly fitted to its .exteriora worm gear (Fig. 15),which is accommodated within the aforementioned housing 138. The lattersupports bowl 125 through a bearing 151 at the bottom, and a bearing 152near the top. Slip bowl 125 together with the driving gear 150 isaccordingly relatively rotatable inside the exterior housing 138.

Referring to Fig. 13, the housing 138 has .a lateral extension 155containing a driving worm 156 for worm gear 150, worm 156 being drivenby a suitable hydraulic motor 157 fastened to housing portion 155.

The'housing portion 155 is connected by the torque arm 29 to thevertically movable cylinder 30 of the hydraulic elevator.

The torque arm comprises a pair of links 160, each consisting of upperand lower link members 161 and 162 joined by a tube 163, pivotallyconnected to ears formed on housing member 155, and extendingsubstantially parallel to and on opposite sides of a line intersectingthe center line of the power tong. The other ends of links 16!) arepivotally connected to the edge portions 164 of a generally quadrantshaped coupling member 165 made up of two spaced parallel plates 166joined by a tube 167'. A pair of links 168, of the same nature of thelinks 160, are pivotally connected to the edge portions 169 of couplingmember 165 which are at right angles to edge portions 164, whereby thelinks 168 are at right angles to the links 160, the links 168 being onopposite sides of a line intersecting the axis of cylinder 30. Theopposite ends of the links 168 are pivotally connected to spaced plates170 welded to the outside of cylinder 30. This torque arm linkageinteracts to resist torque exerted thereon in either direction by thepower tong housing during spinning of the drill pipe thereby. Torquetransmitted to the cylinder 36 is resisted as described hereinafter.

Cylinder 36 (see Fig. 16) has fluid connections 181 and 182. at its topand bottom, and is packed at opposite ends around the piston 31, asindicated at 183 and 184. The piston has an intermediate head or collar135 slid able inside cylinder 30 and furnished with a sealing ring 186.

Cylinder 30 is fitted at its lower end with a collar having a lug 191 onone side carrying a pivot pin 192 on opposite ends of which .arepivotally mounted the two arms of a V-shaped toggle link 193. Agenerally similar V-shaped toggle link 194 is pivotally mounted on theends of a pin 1'95 extending through a lug on base flange 32. The apexend portion of link 194 is bifurcated as at 196 (Fig. 17) to receive theapex end portion of link 193, and these apex end portions of the linksare pivotally connected to one another by pivot pins 201 having handles201 by which they may be withdrawn against holding springs 2112 fortemporary disconnection of the links from one another.

The toggle links 193 and 194 transmit torque exerted on cylinder 30 bythe torque arm 29 to base flange 32 of the elevator and thence to therotary table frame, whether the elevator and power tong is in elevatedor lowered position. The provision for quick disconnection of the togglelinks from one another permits the elevator cylinder, torque arm andpower tong to be readily swung aside from the well hole when desired.

A hydraulic system is provided for feeding hydraulic fluid to andexhausting it from the various'hydraulic cylinders and to the hydraulicmotor for the power tong, manual control valves being provided forcontrolling the flow to and from said cylinders at will from a mastercontrol station or console. In Fig. 1, the operating handies for suchcontrol valves are indicated at 2113, the valves being mounted at thetop of a console unit 2113a located conveniently for the operator.Supply and return fluid lines are indicated at P and R, and the fluidlines between the valves and the hydraulic cylinders heretoforedescribed are designated generally by the numeral 204. The details ofthe hydraulic system will be passed over until after the generaloperation of the drilling machine has been described.

It will be assumed first that additionalstands of drill pipe are to beintroduced into the well hole. Reference being had first to Fig. 18,showing the beginning position, the power tong 28 has been moved to aposition near upper limit of the travel of elevator cylinder 30. Using aconventional drill pipe elevator, indicated diagrammatically at L, thepipe stand 25 has been stabbed through the tong into the coupling box 24of lower pipe stand 23, which is gripped at this time by the rotarytable slips 51. The tong slips 127 are then set about the pipe 25, asshown, and the hydraulic motor of the power tong then operated to spinthe pipe 25 to screw it into the coupling box at 24.

The tong and rotary table slips are then disengaged, and the tonglowered by the hydraulic cylinder 30 of elevator E to the position oiFig. 19. The pipe string is then lowered to the position shown in Fig.19 by the elevator L, stopping above the power tong. The rotary tableslips 51 are then set, the pipe elevator L raised, and the tong elevatorcylinder 30 operated to raise the power tong back to the position ofFig. 18, after which the procedure is repeated.

To remove pipe, a reverse procedure is followed. With the rotary tableslips 51 set, the power tong is lowered by tong elevator cylinder 30 tothe lower limit of travel, as to the position of Fig. 19. The pipeelevator L is then lowered and engaged with the coupling collar 24, therotary table slips 51 are released, and the pipe string then raised byelevator L to the position shown in Fig. 18. The tong elevator E is thenoperated to raise the tong, stopping about two inches short of the upperlimit of travel of elevator cylinder 30, as in Fig. 18. It will be notedthat the pipe string has been stopped with the coupling collar 24 belowthe position to which the tong has been elevated. The tong and rotarytable slips are both set, and the power tong operated to spin the upperpipe section and so unscrew it from coupling box 24. During thisspinning operation, the elevator cylinder 30 is further raised, as laterto be described, just enough for the necessary upward move ment of theupper pipe section as it screws out of the coupling box 24, the two inchremaining travel of the elevator cylinder being provided for thispurpose. The tong slips are then released, the broken out stand of pipestowed, and the procedure repeated.

The typical hydraulic system of the invention is shown in a typicalembodiment in Fig. 20. A hydraulic pump 210, receiving fluid fromreservoir 211, feeds main pressure line 212 leading to and through anopen-center pressure control valve 213. An open-center valve will beunderstood by those skilled in the art to denote a valve which, in itscenter or neutral position, affords a straight-through passage throughthe valve (see Fig. 20a), which passage is blocked when the valve isshifted from center or neutral position.

Line 212, at a point ahead of valve 213, is connected through 3000p.s.i. relief valve 214 to return line 215 leading back to reservoir211, it being understood that pump 210 delivers fluid at 3000 psi. orslightly higher. At a point beyond valve 213, a line 212a receivingpressure fluid from line 212 through said vaive when in neutral position(Fig. 20a), is connected through 200 p.s.i. relief valve 216 to returnline 215.

Line 212a (valve 213 being at neutral) feeds pressure fluid at 200p.s.i. to branch lines 218 and 219 leading to low pressure fluid intakeports of control valves 220 and 221, respectively. As indicated, thevalve 220 has two fluid connections connected by lines 222 and 223 tothe upper and lower ends, respectively, of the operating cylinder 102for the rotary table slips, while the valve 221 has similar fluidconnections connected by lines 224 and 225 to the upper and lower ends,respectively, of the operating cylinder 139 for the tong slips, it beingrecalled that introduction of fluid to the upper ends of the saidcylinders results in elevating and releasing the corresponding sets ofslips 51 and 127.

The valves 220 and 221 have return ports leading via line 226 to returnline 215.

Also, the valves 220 and 221 have high pressure intake connections,receiving pressure fluid at 1200 p.s.i. from a supply line 227 connectedto an outlet port of control valve 213, through which fluid is receivedfrom supply line 212 when valve 213 is in the dotted line positionshown, the pressure in line 227 being held at 1200 p.s.i. by means of1200 p.s.i. relief valve 228 connected between line 227 and return line215.

The several valves are ported to establish alternate flow paths asindicated in full lines and in dotted lines, and it will be understoodthat in a neutral position of each valve, intermediate the two positionsindicated, said alternate paths are both blocked. Taking valve 220 forexample, in the valve position shown in full lines, pressure fluid at200 p.s.i. flows through the valve to line 222 and thence to the upperend of cylinder 102, thus elevating and releasing the slips of therotary table, fluid from the lower end of said cylinder returning toreservoir 211 via line 223, the valve 220, and line 226. When the slipsare to be set, valves 213 and 220 are positioned as indicated in dottedlines, at which time fluid at a higher pressure, e.g., 1200 p.s.i., isconveyed from line 227 through the valve 220 and via line 223 to thelower end of cylinder 102, thus forcing the slips down and inward intoclamping engagement with the pipe string. The high pressure used forsetting the slips will be understood to give tighter clamping of thepipe. In this dotted line position of valve 220, fluid from the upperend of cylinder 102 returns via line 222, valve 220, and line 226.Corresponding operations occur with corresponding manipulations of valve221 to release or set the slips of the power tong.

As a preferred safety feature, there is provided an air pressure systemfor holding the rotary table and power slips in set position when thesource of high pressure hydraulic fluid is cut off by manipulation ofthe control valve 213. An air pressure line 229, carrying air at apressure of for example p.s.i., feeds the air sides of two accumulators230a and 23Gb through two check valves, as shown, and the hydraulicsides of these accumulators are connected to the lines 223 and 225,respectively, leading to the bottom ends of the power cylinders for therotary table and power tong slips. The accumulators may be of aconventional type comprising a movable piston or membrane between itsair and hydraulic ends. With the valves 220 and 221 in the full linepositions, hydraulic fluid is exhausted from the accumulators throughsaid valves to the return line 226, as will be seen, and the accumulatorpistons will advance correspondingly under the applied air pressure.Now, when the valves 220 or 221 are turned to their dotted linepositions, and control valve 213 has also been placed in its dotted lineposition, high pressure hydraulic fluid (1200 p.s.i.), is fed to thelower ends of power cylinders 102 and 139 to set the slips, as beforedescribed, and this high pressure fluid also feeds the accumulators,moving the accumulator pistons back, and raising both the air andhydraulic sides of the accumulator to 1200 p.s.i. It now the controlvalve 213 should be turned to some other position, the 1200 p.s.i.hydraulic pressure fluid supply is cut 011 from the power cylinders 102and 139 by which the slips are being held tightly in set condition.Under such conditions, the air trapped behind the accumulator pistons at1200 p.s.i. is enabled to expand sufliciently to assure maintenance ofhigh pressure on the hydraulic fluid within the power cylinders 102 and139, and there is thus positive assurance that the slips will notrelease and drop the pipe.

With control valve 213 in its neutral position, as in Fig. 20a, pressurefluid line 212a receives fluid therethrough and carries it at pressureof 200 p.s.i. owing to relief valve 216. This line 212a feeds fluid atsuch pressure to either of two pressure fluid intakes ports of aselector valve 231 controlling introduction of fluid to the cylinder 30of tong elevator E. The valve 231 has one outlet port connected via line232 leading to one side of counter balance valve 233, the other side ofwhich .is connected to the upper end of elevator cylinder 30. The valve231 has a second outlet port connected via line 234 to the lower end ofelevator cylinder 30. The valve 231 has also a return fluid portconnected to return line 215, and an adjustable relief valve 235 isconnected between line 234 and return line 215. The valve 231 is portedto establish alternate flow paths as shown in full and dotted lines, andit will be understood that in a third or intermediate position of thevalve all flow through the valve is blocked. In the flow path shown infull lines, fluid at 200 p.s.i. is fed through line 232 and counterbalance valve 233 to the upper end of elevator cylinder 30 to elevatethe power tong, while fluid from the lower end of said cylinder isexhausted via line 234 and the valve 231 to return line 215.

To lower the power tong, valve 231 is shifted to the alternate (dottedline) position, so that pressure fluid from line 212a passes throughsaid valve according to the flow paths shown in dotted lines to feed thelower end of cylinder 30 via line 234, fluid from the upper end ofcylinder 30 being exhausted via the counter balance valve 233, line 232,valve 231, and return line 215.

The counter balance valve 233 is of a known check valved type, nospecific example of which need be shown herein, adapted to pass fluidfreely in the direction toward the power cylinder, but to hold a limitedback pressure for the return direction. The valve is so adjusted thatthis back pressure is below the 200 p.s.i. input level, but sufiicientto counter balance the weight of the elevator cylinder 30 and power tongcarried by the latter. Accordingly, valve 231 being in the dotted lineposition, or in neutral position, the elevator and power tong will besupported in elevated position by fluid trapped in the upper end ofcylinder 30 at the pressure determined by the setting of the counterbalance valve. However, with valve 231 in the dotted line position,pressure fluid at 200 p.s.i. supplied via valve 231 and line 234 to thelower end of the cylinder 30 will create a downward differential offorce and so lower the cylinder and power tong, the fluid trapped in theupper end of the cylinder 30 being forced out through the counterbalance valve at a pressure higher than the setting of the latter forrelief. Exhaust flow accordingly takes place from the upper end ofcylinder 30 through the valve 233, line 232 and valve 231 to return, thecylinder 30 and power tong being, however, counter balanced throughoutowing to the back pressure always held by the valve 233. The reliefvalve 235 has a pressure relief setting below 200 p.s.i. but higher thanthe setting of the counter balance valve 233, so that sufiicientpressure can be developed in line 234 and the bottom end of cylinder 30to assure exhaust of fluid through counter balance valve 233, while atthe same time the setting of this relief valve is such as to limit thepressure delivered to cylinder 30 to a reasonable level.

The hydraulic power tong motor 157 has two fluid connections servingalternately as inlet and outlet, and these are fed from fluid lines 250and 251 leading from ports of a control valve 252. The latter has twointake connections, one fed with pressure fluid at high pressure, e.g.,3000 p.s.i., from line 253 leading from one outlet port of control valve213, which is ported, as indicated, so that when positioned in the fullline position, it feeds line 253 from supply line 212. The other intakeconnection of valve 252 is supplied with fluid at 1200 p.s.i. via line254 and line 227 when valve 213 is in the position indicated in dottedlines. Arrangements are so made that motor 157 receives fluid through3000 p.s.i. lines 250 and 253 for its direction of rotation for breakingthe pipe joints, which requires the most effort.

Accordingly, assuming that it is desired to break a coupling joint,valves 213 and 252 are positioned as shown in full lines, so as to feedhigh pressure fluid to tong motor 157, causing the latter to rotate thepower '10 tong in the direction to unscrew the pipe section clamped bythe tong slips from the pipe section clamped by the rotary table slips.The fluid exhausted from the tong motor flows via line 251, valve 252,and line 256 to line 212a, to be passed through relief valve 216 toreturn line 215. A part of the exhausted fluid, maintained at 200p.s.i., flows from line 212a through valve 231, positioned at this timein the full line position, and thence through line 232 and counterbalance valve 233 to the upper end of elevator cylinder 30, elevatingthe latter in correspondence with the rise of the upper pipe section 7owing to the latter being unscrewed upwardly out of the coupling. Acorresponding amount of fluid from the lower end of cylinder 30 is atthe same time discharged to return, as will be understood.

To make joint, valves 213 and 252 are positioned in accordance with thedotted line indications, as is tong elevator control valve 231. Fluidfrom supply line 212 then passes through valve 213 to line 227,maintained at 1200 p.s.i. thence flowing through line 254, control valve252 and line 251 and to the tong motor, driving the latter in thereverse direction, i.e., in the direction to screw the upper pipesection into the coupling box on the upper end of the lower pipesection. Fluid exhausted from the tong motor then flows via line 250,valve 252, and line 256 to line 212a and return via relief valve 216.Fluid is at the same time supplied to the lower end of elevator cylinder30 from line 212a via valve 231, with the result that the elevator islowered by the amount in correspondence with the fall of the pipesection gripped by the power tongs owing to said pipe section beingscrewed down into the coupling box.

Operation It will be assumed first that additional stands of drill pipeare to be added to the lower pipe stand 23 which is gripped at this timeby the rotary table slips 51. -It will also be assumed that all of thecontrol valves of the apparatus are in their neutral positions whereinflow through all of the valves, except valve 213, is blocked. In theneutral position of valve 213, fluid at 200 p.s.i. is, of course,delivered via line 212a to the elevator control valve 231, via lines 218and 219 to the slip control valves 220 and 221, and via line 256 to thetong motor control valve 252.

The power tong 28 is first elevated to a position (Fig. 18) near theupper limit of travel of the elevator cylinder 30 by operation of theelevator control valve 231 to its full line position wherein fluid .at200 p.s.i. from line 212a is admitted to the upper end of the cylinderand fluid is exhausted from the lower end of the cylinder to the returnline 215 in the manner already described. Valve 231 is then returned toits neutral or closed position.

The tong slip control valve 221 is now operated to its full lineposition to release the tong slips. Using the drill pipe elevator L, theupper pipe stand 25 is stabbed through the tong into the coupling box 24of the lower pipe stand 23. The tong slips 127 are then set about theupper pipe stand 25 by operation of valve 213 and tong slip controlvalve 221 to their dotted line positions wherein fluid at 1200 p.s.i.flows from line 227, to the lower end of the tong slip control cylinder13-9 and fluid is exhausted from the upper end of the cylinder to thereturn line 215 in the manner described. Valve 221 may, if desired, nowbe returned to its neutral or closed position, in which case accumulator23012 retains the tong slips set.

With valve 213 retained in its dotted line position, the tong motor andelevator control valves 252 and 231 are operated to their dotted linepositions. The tong motor 157 is .now driven in a direction to threadthe upper pipe stand 25 into the coupling box 24 of the lower pipe stand23. As previously mentioned, fluid exhausted from the motor is deliveredto the lower end of the elevator cylinder 30 to effect loweringof thetong and upper pipe stand 1 1 gripped thereby during threading of thelatter into the lower pipe stand.

After the upper pipe stand has been fully threaded into the lower pipestand, the valves 213, 231 and 252 are returned to their neutralpositions and the slip control valves 220 and 221 are operated to theirfull line positions to admit fluid at 200 p.s.i. from line 212a to theupper ends of the slip control cylinders 102 and 139 and thereby releasethe rotary table and tong slip.

The tong elevator E is now lowered to the position of Fig. 19, whereinthe elevator cylinder is at the lower limit of its travel, by operationof the elevator valve 231 to its dotted line position wherein fluid at200 p.s.i. from line 212a is admitted to the lower end of the elevatorcylinder 39. The elevator valve 231 is then returned to its neutralposition.

The pipe string is then lowered to the position of Fig. 19 by theelevator L, and the rotary table slips are reset by operation of thevalves 213 and 220 to their dotted line positions to regrip the pipestand. The valves 213 and 220 are then returned to their neutralpositions, the accumulator 23ila retaining the rotary table slips set.

After the pipe elevator L has been raised clear of the apparatus,elevator control valve 231 is again operated to its full line positionto elevate the power tong to its starting position of Fig. 18, whereuponthe foregoing steps may be repeated to add another pipe stand, ifdesired.

To remove a pipe, a reverse procedure is followed. Thus, with the rotarytable slips 51 set to grip the pipe stand, the power tong is lowered tothe lower limit of travel of the elevator cylinder 30 by operation ofthe elevator control valve 231 to its dotted line position with thevalve 23 in its neutral position. The pipe elevator L is then loweredand engaged with the coupling collar 24 on the pipe stand, the rotarytable slips 51 are released by operation of the valve 220 to its solidline position, and the pipe string is raised to the position of Fig. 18by the elevator L.

The elevator valve 231 is then operated to its full line position toelevate the power tong to a position about two inches short of the upperlimit of travel of the elevator cylinder 30 (Fig. 18). Valve 231 is thenreturned to its neutral position.

Valves 213, 220 and 221 are now operated to their dotted line positionsto admit fluid at 1200 p.s.i. from the line 227 to the lower ends of theslip control cylinders 102 and 139 and thereby cause setting of therotary table and tong slips. The slip control valves 220 and 221 maythen be returned to their neutral positions, in which case theaccumulators 236a and 23012 retain the slips set.

Valves 213, 231 and 252 are now operated to their full line positions toeffect driving of the tong motor 157 in a direction to unthread theupper pipe section 25 from the coupling box 24. Fluid exhausted from thetong motor is delivered to the upper end of the elevator cylinder 3i),in the manner previously described, to cause elevating of the upper pipesection as the latter threads out of the coupling box 24. i

The tong slips are then released, the broken out stand of pipe stowed,and the procedure repeated.

The complete operation of the system should now be evident. It will beseen that a system has been provided by which all the operationsincidental to running in or running out pipe can be carried out by powerdevices under the control of a single operator, with the aid of a singleworkman in the derrick to handle the stands of pipe as they are added toor removed from the string.

We claim:

1. In a hydraulic tong elevator, the combination comprising a horizontaltable, a vertical piston and cylinder assembly, a power tong on onemember of said assembly, means mounting the other member of saidassembly on said table, a source of pressure fluid at a predeterminedpressure, a return pressure fluid line, a control valve for selectivelyconnecting said source of pressure fluid to either end of said cylinderand the other end of said cylinder to said return line, a counterbalance check valve between said control valve and the end of saidcylinder which causes elevation of said tong, said counter balance checkvalve passing fluid toward said cylinder without restriction and beingset to impose a predetermined back pressure against reverse flow offluid just sufficient to counter: balance the weight of said one memberand the tong carried thereby.

2. In apparatus of the character described, a power tong includingrotary pipe gripping means and means for driving the gripping means inrotation, a torque arm supporting said power tong, and a hydraulicelevator for elevating and lowering said torque arm betweenpredetermined limits comprising a vertically disposed connecting rodhaving mounting means at its lower end and provided with an enlargedpiston, a cylinder slidably fitted on said piston and having reducedends slidably fitted on said rod, means for supplying hydraulic fluid toand exhausting fluid from opposite ends of said cylinder, means on saidcylinder supporting said torque arm, a pair of torque resisting links,one of which is pivotally connected at one end to said cylinder, theother of which is pivotally connected at one end to said connecting rodbelow said cylinder, and means pivotally connecting the remaining endsof said links to one another.

3. The subject matter of claim 2, wherein the means pivotally connectingthe two ends of the links to one another includes quick detachment meansby which the links may be readily disconnected from one another topermit rotation of the cylinder on the connecting rod.

4. In oil well machinery for making and breaking screw thread joints inrunning thread-jointed strings into and out of oil wells, thecombination of: a stationary frame to be located at the well head, apower tong positioned over said frame and including a reversiblepressure fluid drive motor, reversible, pressure fluid operated elevatormeans supporting said power tong on said frame for vertical movement ofsaid tong relative to said frame, and selectively operable control meansfor admitting pressure fluid to said motor to etfect selective operationof the latter in reversed directions and exhausting pressure fluid fromsaid motor to said elevator means to raise said tong during operation ofsaid motor in one direction and lower said tong during operation of saidmotor in the other direction.

5. In oil well machinery for making and breaking screw thread joints inrunning thread-jointed strings into and out of oil wells, thecombination off: a stationary frame to be located at the well head, apower tong positioned above said frame, said power tong including areversible pressure fluid motor operable in one direction to make ajoint and in the other direction to break a joint, means for selectivelyfeeding pressure fluid to said motor to effect operation of the latterin opposite directions, elevator means supporting said tong on saidframe for vertical movement relative to the latter, said elevator meansincluding a piston and cylinder assembly, one member of which is mountedon said frame and the other member of which carries said tong, and meanscomprising pressure fluid connections and valve control means thereinfor selectively feeding exhaust pressure fluid from said motor to eitherend of said cylinder and exhausting the opposite end of the cylinder tolower said tong a predetermined distance during operation of said motorin said one direction and raise said tong a predetermined distanceduring operation of said motor in the opposite direction.

6. In well machinery for running screw thread jointed strings into andout of wells, the combination of: a stationary frame to be located at awell head; lower power operated gripping means on the frame forreceiving a string extending into the well and releasably gripping saidstring a distance below a given joint thereof with suflicient force tosupport the string in the axial direction and restrain the stringagainst rotation under torques at least as great as that encountered inmaking and breaking said joints; a power operated tong on said frameincluding upper rotary power operated gripping means for receiving andreleasably gripping the string extending through the lower grippingmeans, a reversible power operated motor means for rotating said uppergripping means to make and break joints in the string, and a poweroperated elevator means supporting said upper gripping means on theframe for vertical movement between a raised position wherein the uppergripping means is located at a level sufiiciently above the lowergripping means to enable said given joint in the string to ocupyaposition between said upper and lower gripping means whereby said uppergripping means may grip the string above said given joint, and a loweredposition wherein the upper gripping means is located sufiiciently closeto the lower gripping means as to be disposed below said given joint inthe string; a source of power for said power operated means; and controlmeans for said power operated means comprising an operators controlstation including control members for selectively setting and releasingeach of said gripping means, operating said elevator to raise and lowerthe upper gripping means, and operating said motor in oppositedirections.

7. The subject matter of claim 6 wherein said power operated means arehydraulically operated, said power source comprises a supply ofhydraulic fluid under pressure, said control means comprises a hydraulicsystem connected to said hydraulically operated means, and said controlmembers comprise a control valve to selectively set and release saidgripping means, a control valve to selectively raise and lower saidupper gripping means, a control valve to reverse said motor,respectively, and a selector valve for controlling the flow of hydraulicfluid rom said supply to said control valves.

8. The subject matter of claim 7 including pneumatic accumulator meansconnected to said gripping means to retain the latter set when thecontrol valve associated with said gripping means is positioned to setthe latter means.

9. In well machinery for running screw thread jointed strings into andout of wells, the combination of: a stationary frame to be located at awell head; lower power operated gripping means on the frame forreceiving a string extending into the well and releasably gripping saidstring a distance below a given joint thereof; a power operated tong onsaid frame including upper rotary gripping means for receiving andreleasably gripping the string extending through the lower grippingmeans, a reversible power operated motor means for rotating said uppergripping means to make and break joints in the string, and a poweroperated elevator means supporting said upper gripping means on theframe for vertical movement between a raised position wherein the uppergripping means is located at a level sufiiciently above the lowergripping means to enable said upper gripping means to grip the stringabove said given joint, and a lowered position wherein the uppergripping means is located sufficiently close to the lower gripping meansso as to be disposed below said given joint; 21 source of power for saidpower operated means; and control means for said power operated meanscomprising a master control station including selectively operable meansfor selectively setting and releasing each of said upper and lowergripping means, operating said elevator to raise and lower the uppergripping means, and operating said motor in either direction.

10. In well machinery for making and breaking screw thread joints inrunning thread-jointed strings into and out of wells, the combinationof: a stationary frame to be located at a well head, upper and lowergripping means on said frame for gripping a thread-jointed stringextending into the well above and below a given joint, said uppergripping means being rotatable and vertically movable with respect tothe lower gripping means, hydraulic means for vertically moving saidupper gripping means toward and away from the lower gripping means, areversible hydraulic motor for driving said upper gripping means ineither direction of rotation, and a hydraulic control system forselectively supplying hydraulic fluid to said motor for operating thelatter in one direction and simultaneously supplying hydraulic fluid tothe hydraulic means in a direction to move said upper gripping meanstoward said lower gripping means at a rate proportional to the rate ofrotation of the motor, and supplying hydraulic fluid to said motor foroperating the latter in the opposite direction and simultaneouslysupplying hydraulic fluid to the hydraulic means in a direction to movesaid upper gripping means away from said lower gripping means at a rateproportional to the rate of rotation of the upper gripping means.

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